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Sprinklers vs rotors

I've got 21 zones of sprinklers and rotary spray heads. The sprinklers are RainBird and the rotors are PGP. I notice that the zones that were installed for the rotors were 4 to 5, mostly 4 rotors, that's fine at 8 to 10 GPM at 60 psi. However, the sprinklers are rated at 30 psi and the zones have anywhere from 5 to 8 sprinklers and they seem to range around 1.5 to over 2 GPM at 30 psi. When I turn down the sprinklers to only cover the area they are supposed to cover (like a van-8 to cover 8') does that mean when I'm giving them 60 psi, they are acting like they really only are putting out their rated 1.5-2 GPM? I'm trying to figure out what the GPM I'm really getting per zone, especially with the sprinklers. This has to do with my other post on the pump forum about a new sub pump I'm putting in.

If you just trying to figure out the flow of each zone. Simply just watch your water meter for each zone.

If you are trying to figure out the flow of each head then you will need a pedo tube gauge to measure accurate head pressure. Then you will use the pho nozzle chart to deter main the flow for what nozzle you have in the PGP.

On a PGP the flow does not change no matter how far the radius or arc is. The only thing that will change flow on. PGP is pressure or a nozzle change.

Hard to say. Even the performance table doesn't go above 30 psi. They even put a disclaimer on the data they provide. Reducing the distance through the radius adjistment screw will reduce flow, but to say it will match the 30psi figures is anybody's guess. My theory is that it would be close, but determining the flow accurately according to the arc adjustment would be difficult, since the VAN nozzles are, well, variable.